The present invention relates to a reference voltage signal generator, and more particularly, to a reference voltage signal generator capable of generating a constant reference voltage signal regardless of a temperature change by effectively compensating voltage variation due to a change in the temperature.
A reference voltage signal generator is a device that generates a voltage signal used as a reference voltage signal of memory devices, e.g., flash memory devices adopting various levels of voltage signals generated from one power supply voltage signal.
Generally, the reference voltage signal generator must generate constant reference voltage signals even if the output voltage signal of the power supply varies.
Referring to FIG. 1, a conventional reference voltage signal generator comprises a first voltage signal generating unit 110, a regulation sense amplifier 120, a voltage distributing unit 130 and a second voltage signal generating unit 140. The first voltage signal generating unit 110 receives a power supply voltage signal in response to an enable signal En and generates a first voltage signal V11 of a predetermined value.
The regulation sense amplifier 120 receives the first voltage signal V11 from the first voltage signal generating unit 110 in response to the enable signal En and generates a regulated voltage signal Vr to the voltage distributing unit 130. Furthermore, the regulation sense amplifier 120 also receives a feedback voltage signal Vfb from the voltage distributing unit 130 and generates the constant regulation voltage signal Vr independently of any change in the voltage signal level of the power supply.
The second voltage signal generating unit 140, which has the same configuration as that of the first voltage signal generating unit 110, receives the constant regulation voltage signal Vr and generates a reference voltage signal Vref which is stable and constant. In FIG. 1, the numeral references xe2x80x98I100xe2x80x99 and xe2x80x98S100xe2x80x99 are an inverter and a switching element, respectively.
Although the conventional reference voltage signal generator can generates a constant reference voltage signal Vref independently of any change in the voltage signal variation of the power supply, the constant reference voltage signal Vref may be changed by effect of a change of temperature.
That is, resistors R11 and R12 of the voltage distributing unit 130 do not reflect the temperature change, therefore it is difficult to compensate the voltage signal variation due to the change in temperature.
It is, therefore, an object of the present invention to provide a reference voltage signal generator capable of generating a constant reference voltage signal regardless of a change in temperature, by compensating voltage signal change due to the temperature variation.
It is, therefore, another object of the present invention to provide a reference voltage signal generator comprising a variable resistor for compensating the voltage signal variation according to a change in temperature, in order to produce a constant reference voltage signal, even if the temperature changes.
In accordance with another aspect of the present invention, there is provided a reference voltage signal generating device comprising: a voltage signal generating unit receiving a power supply voltage signal and generating a first voltage signal; a regulation sense amplifier generating a regulation voltage signal by regulating the first voltage signal according to the variation of the power supply voltage signal; and a voltage distributing unit including a variable resistor for compensating a voltage signal variation according to a change in temperature, wherein the voltage distributing unit distributes the regulation voltage signal and outputs a feedback voltage signal dependent on a temperature to the regulation sense amplifier, and a reference voltage signal independent of the temperature.